Source for javax.swing.JList

   1: /* JList.java --
   2:    Copyright (C) 2002, 2003, 2004, 2005, 2006,  Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package javax.swing;
  40: 
  41: import java.awt.Color;
  42: import java.awt.Component;
  43: import java.awt.ComponentOrientation;
  44: import java.awt.Cursor;
  45: import java.awt.Dimension;
  46: import java.awt.Font;
  47: import java.awt.FontMetrics;
  48: import java.awt.Point;
  49: import java.awt.Rectangle;
  50: import java.awt.event.FocusListener;
  51: import java.beans.PropertyChangeEvent;
  52: import java.beans.PropertyChangeListener;
  53: import java.util.Locale;
  54: import java.util.Vector;
  55: 
  56: import javax.accessibility.Accessible;
  57: import javax.accessibility.AccessibleComponent;
  58: import javax.accessibility.AccessibleContext;
  59: import javax.accessibility.AccessibleRole;
  60: import javax.accessibility.AccessibleSelection;
  61: import javax.accessibility.AccessibleState;
  62: import javax.accessibility.AccessibleStateSet;
  63: import javax.swing.event.ListDataEvent;
  64: import javax.swing.event.ListDataListener;
  65: import javax.swing.event.ListSelectionEvent;
  66: import javax.swing.event.ListSelectionListener;
  67: import javax.swing.plaf.ListUI;
  68: import javax.swing.text.Position;
  69: 
  70: /**
  71:  * <p>This class is a facade over three separate objects: {@link
  72:  * javax.swing.ListModel}, {@link javax.swing.ListSelectionModel} and
  73:  * {@link javax.swing.plaf.ListUI}. The facade represents a unified "list"
  74:  * concept, with independently replacable (possibly client-provided) models
  75:  * for its contents and its current selection. In addition, each element in
  76:  * the list is rendered via a strategy class {@link
  77:  * javax.swing.ListCellRenderer}.</p>
  78:  *
  79:  * <p>Lists have many properties, some of which are stored in this class
  80:  * while others are delegated to the list's model or selection. The
  81:  * following properties are available:</p>
  82:  *
  83:  * <table>
  84:  * <tr><th>Property                       </th><th>Stored in</th><th>Bound?</th></tr>
  85:  * <tr><td>accessibleContext              </td><td>list     </td><td>no    </td></tr>
  86:  * <tr><td>anchorSelectionIndex           </td><td>selection</td><td>no    </td></tr>
  87:  * <tr><td>cellRenderer                   </td><td>list     </td><td>yes   </td></tr>
  88:  * <tr><td>dragEnabled                    </td><td>list     </td><td>no    </td></tr>
  89:  * <tr><td>firstVisibleIndex              </td><td>list     </td><td>no    </td></tr>
  90:  * <tr><td>fixedCellHeight                </td><td>list     </td><td>yes   </td></tr>
  91:  * <tr><td>fixedCellWidth                 </td><td>list     </td><td>yes   </td></tr>
  92:  * <tr><td>lastVisibleIndex               </td><td>list     </td><td>no    </td></tr>
  93:  * <tr><td>layoutOrientation              </td><td>list     </td><td>yes   </td></tr>
  94:  * <tr><td>leadSelectionIndex             </td><td>selection</td><td>no    </td></tr>
  95:  * <tr><td>maxSelectionIndex              </td><td>selection</td><td>no    </td></tr>
  96:  * <tr><td>minSelectionIndex              </td><td>selection</td><td>no    </td></tr>
  97:  * <tr><td>model                          </td><td>list     </td><td>yes   </td></tr>
  98:  * <tr><td>opaque                         </td><td>list     </td><td>no    </td></tr>
  99:  * <tr><td>preferredScrollableViewportSize</td><td>list     </td><td>no    </td></tr>
 100:  * <tr><td>prototypeCellValue             </td><td>list     </td><td>yes   </td></tr>
 101:  * <tr><td>scrollableTracksViewportHeight </td><td>list     </td><td>no    </td></tr>
 102:  * <tr><td>scrollableTracksViewportWidth  </td><td>list     </td><td>no    </td></tr>
 103:  * <tr><td>selectedIndex                  </td><td>selection</td><td>no    </td></tr>
 104:  * <tr><td>selectedIndices                </td><td>selection</td><td>no    </td></tr>
 105:  * <tr><td>selectedValue                  </td><td>model    </td><td>no    </td></tr>
 106:  * <tr><td>selectedValues                 </td><td>model    </td><td>no    </td></tr>
 107:  * <tr><td>selectionBackground            </td><td>list     </td><td>yes   </td></tr>
 108:  * <tr><td>selectionEmpty                 </td><td>selection</td><td>no    </td></tr>
 109:  * <tr><td>selectionForeground            </td><td>list     </td><td>yes   </td></tr>
 110:  * <tr><td>selectionMode                  </td><td>selection</td><td>no    </td></tr>
 111:  * <tr><td>selectionModel                 </td><td>list     </td><td>yes   </td></tr>
 112:  * <tr><td>UI                             </td><td>list     </td><td>yes   </td></tr>
 113:  * <tr><td>UIClassID                      </td><td>list     </td><td>no    </td></tr>
 114:  * <tr><td>valueIsAdjusting               </td><td>list     </td><td>no    </td></tr>
 115:  * <tr><td>visibleRowCount                </td><td>list     </td><td>no    </td></tr>
 116:  * </table> 
 117:  *
 118:  * @author Graydon Hoare (graydon@redhat.com)
 119:  */
 120: 
 121: public class JList extends JComponent implements Accessible, Scrollable
 122: {
 123: 
 124:   /**
 125:    * Provides accessibility support for <code>JList</code>.
 126:    */
 127:   protected class AccessibleJList extends AccessibleJComponent
 128:     implements AccessibleSelection, PropertyChangeListener,
 129:                ListSelectionListener, ListDataListener
 130:   {
 131: 
 132:     /**
 133:      * Provides accessibility support for list elements in <code>JList</code>s.
 134:      */
 135:     protected class AccessibleJListChild extends AccessibleContext
 136:       implements Accessible, AccessibleComponent
 137:     {
 138: 
 139:       /**
 140:        * The parent list.
 141:        */
 142:       JList parent;
 143: 
 144:       /**
 145:        * The index in the list for that child.
 146:        */
 147:       int listIndex;
 148: 
 149:       /**
 150:        * The cursor for this list child.
 151:        */
 152:       // TODO: Testcases show that this class somehow stores state about the
 153:       // cursor. I cannot make up though how that could affect
 154:       // the actual list.
 155:       Cursor cursor = Cursor.getDefaultCursor();
 156: 
 157:       /**
 158:        * Creates a new instance of <code>AccessibleJListChild</code>.
 159:        *
 160:        * @param list the list of which this is an accessible child
 161:        * @param index the list index for this child
 162:        */
 163:       public AccessibleJListChild(JList list, int index)
 164:       {
 165:         parent = list;
 166:         listIndex = index;
 167:       }
 168: 
 169:       /**
 170:        * Returns the accessible context of this object. Returns
 171:        * <code>this</code> since <code>AccessibleJListChild</code>s are their
 172:        * own accessible contexts.
 173:        *
 174:        * @return the accessible context of this object, <code>this</code>
 175:        */
 176:       public AccessibleContext getAccessibleContext()
 177:       {
 178:         return this;
 179:       }
 180: 
 181:       /**
 182:        * Returns the background color for this list child. This returns the
 183:        * background of the <code>JList</code> itself since the background
 184:        * cannot be set on list children individually
 185:        *
 186:        * @return the background color for this list child
 187:        */
 188:       public Color getBackground()
 189:       {
 190:         return parent.getBackground();
 191:       }
 192: 
 193:       /**
 194:        * Calling this method has no effect, since the background color cannot be
 195:        * set on list children individually.
 196:        *
 197:        * @param color not used here.
 198:        */
 199:       public void setBackground(Color color)
 200:       {
 201:         // Calling this method has no effect, since the background color cannot
 202:         // be set on list children individually.
 203:       }
 204: 
 205:       /**
 206:        * Returns the foreground color for this list child. This returns the
 207:        * background of the <code>JList</code> itself since the foreground
 208:        * cannot be set on list children individually.
 209:        *
 210:        * @return the background color for this list child
 211:        */
 212:       public Color getForeground()
 213:       {
 214:         return parent.getForeground();
 215:       }
 216: 
 217:       /**
 218:        * Calling this method has no effect, since the foreground color cannot be
 219:        * set on list children individually.
 220:        *
 221:        * @param color not used here.
 222:        */
 223:       public void setForeground(Color color)
 224:       {
 225:         // Calling this method has no effect, since the foreground color cannot
 226:         // be set on list children individually.
 227:       }
 228: 
 229:       /**
 230:        * Returns the cursor for this list child.
 231:        *
 232:        * @return the cursor for this list child
 233:        */
 234:       public Cursor getCursor()
 235:       {
 236:         // TODO: Testcases show that this method returns the cursor that has
 237:         // been set by setCursor. I cannot make up though how that could affect
 238:         // the actual list.
 239:         return cursor;
 240:       }
 241: 
 242:       /**
 243:        * Sets the cursor for this list child.
 244:        */
 245:       public void setCursor(Cursor cursor)
 246:       {
 247:         this.cursor = cursor;
 248:         // TODO: Testcases show that this method returns the cursor that has
 249:         // been set by setCursor. I cannot make up though how that could affect
 250:         // the actual list.
 251:       }
 252: 
 253:       /**
 254:        * Returns the font of the <code>JList</code> since it is not possible to
 255:        * set fonts for list children individually.
 256:        *
 257:        * @return the font of the <code>JList</code>
 258:        */
 259:       public Font getFont()
 260:       {
 261:         return parent.getFont();
 262:       }
 263: 
 264:       /**
 265:        * Does nothing since it is not possible to set the font on list children
 266:        * individually.
 267:        *
 268:        * @param font not used here
 269:        */
 270:       public void setFont(Font font)
 271:       {
 272:         // Does nothing since it is not possible to set the font on list
 273:         // children individually.
 274:       }
 275: 
 276:       /**
 277:        * Returns the font metrics for the specified font. This method forwards
 278:        * to the parent <code>JList</code>. 
 279:        *
 280:        * @param font the font for which the font metrics is queried
 281:        *
 282:        * @return the font metrics for the specified font
 283:        */
 284:       public FontMetrics getFontMetrics(Font font)
 285:       {
 286:         return parent.getFontMetrics(font);
 287:       }
 288: 
 289:       /**
 290:        * Returns <code>true</code> if the parent <code>JList</code> is enabled,
 291:        * <code>false</code> otherwise. The list children cannot have an enabled
 292:        * flag set individually.
 293:        *
 294:        * @return <code>true</code> if the parent <code>JList</code> is enabled,
 295:        *         <code>false</code> otherwise
 296:        */
 297:       public boolean isEnabled()
 298:       {
 299:         return parent.isEnabled();
 300:       }
 301: 
 302:       /**
 303:        * Does nothing since the enabled flag cannot be set for list children
 304:        * individually.
 305:        *
 306:        * @param b not used here
 307:        */
 308:       public void setEnabled(boolean b)
 309:       {
 310:         // Does nothing since the enabled flag cannot be set for list children
 311:         // individually.
 312:       }
 313: 
 314:       /**
 315:        * Returns <code>true</code> if this list child is visible,
 316:        * <code>false</code> otherwise. The value of this property depends
 317:        * on {@link JList#getFirstVisibleIndex()} and
 318:        * {@link JList#getLastVisibleIndex()}.
 319:        *
 320:        * @return <code>true</code> if this list child is visible,
 321:        *         <code>false</code> otherwise
 322:        */
 323:       public boolean isVisible()
 324:       {
 325:         return listIndex >= parent.getFirstVisibleIndex()
 326:                && listIndex <= parent.getLastVisibleIndex();
 327:       }
 328: 
 329:       /**
 330:        * The value of the visible property cannot be modified, so this method
 331:        * does nothing.
 332:        *
 333:        * @param b not used here
 334:        */
 335:       public void setVisible(boolean b)
 336:       {
 337:         // The value of the visible property cannot be modified, so this method
 338:         // does nothing.
 339:       }
 340: 
 341:       /**
 342:        * Returns <code>true</code> if this list child is currently showing on
 343:        * screen and <code>false</code> otherwise. The list child is showing if
 344:        * it is visible and if it's parent JList is currently showing.
 345:        *
 346:        * @return <code>true</code> if this list child is currently showing on
 347:        *         screen and <code>false</code> otherwise
 348:        */
 349:       public boolean isShowing()
 350:       {
 351:         return isVisible() && parent.isShowing();
 352:       }
 353: 
 354:       /**
 355:        * Returns <code>true</code> if this list child covers the screen location
 356:        * <code>point</code> (relative to the <code>JList</code> coordinate
 357:        * system, <code>false</code> otherwise.
 358:        *
 359:        * @return <code>true</code> if this list child covers the screen location
 360:        *         <code>point</code> , <code>false</code> otherwise
 361:        */
 362:       public boolean contains(Point point)
 363:       {
 364:         return getBounds().contains(point);
 365:       }
 366: 
 367:       /**
 368:        * Returns the absolute screen location of this list child.
 369:        *
 370:        * @return the absolute screen location of this list child
 371:        */
 372:       public Point getLocationOnScreen()
 373:       {
 374:         Point loc = getLocation();
 375:         SwingUtilities.convertPointToScreen(loc, parent);
 376:         return loc;
 377:       }
 378: 
 379:       /**
 380:        * Returns the screen location of this list child relative to it's parent.
 381:        *
 382:        * @return the location of this list child relative to it's parent
 383:        *
 384:        * @see JList#indexToLocation(int)
 385:        */
 386:       public Point getLocation()
 387:       {
 388:         return parent.indexToLocation(listIndex);
 389:       }
 390: 
 391:       /**
 392:        * Does nothing since the screen location cannot be set on list children
 393:        * explictitly.
 394:        *
 395:        * @param point not used here
 396:        */
 397:       public void setLocation(Point point)
 398:       {
 399:         // Does nothing since the screen location cannot be set on list children
 400:         // explictitly.
 401:       }
 402: 
 403:       /**
 404:        * Returns the bounds of this list child.
 405:        *
 406:        * @return the bounds of this list child
 407:        *
 408:        * @see JList#getCellBounds(int, int)
 409:        */
 410:       public Rectangle getBounds()
 411:       {
 412:         return parent.getCellBounds(listIndex, listIndex);
 413:       }
 414: 
 415:       /**
 416:        * Does nothing since the bounds cannot be set on list children
 417:        * individually.
 418:        *
 419:        * @param rectangle not used here
 420:        */
 421:       public void setBounds(Rectangle rectangle)
 422:       {
 423:         // Does nothing since the bounds cannot be set on list children
 424:         // individually.
 425:       }
 426: 
 427:       /**
 428:        * Returns the size of this list child.
 429:        *
 430:        * @return the size of this list child
 431:        */
 432:       public Dimension getSize()
 433:       {
 434:         Rectangle b = getBounds();
 435:         return b.getSize();
 436:       }
 437: 
 438:       /**
 439:        * Does nothing since the size cannot be set on list children
 440:        * individually.
 441:        *
 442:        * @param dimension not used here
 443:        */
 444:       public void setSize(Dimension dimension)
 445:       {
 446:         // Does nothing since the size cannot be set on list children
 447:         // individually.
 448:       }
 449: 
 450:       /**
 451:        * Returns <code>null</code> because list children do not have children
 452:        * themselves
 453:        *
 454:        * @return <code>null</code>
 455:        */
 456:       public Accessible getAccessibleAt(Point point)
 457:       {
 458:         return null;
 459:       }
 460: 
 461:       /**
 462:        * Returns <code>true</code> since list children are focus traversable.
 463:        *
 464:        * @return true
 465:        */
 466:       public boolean isFocusTraversable()
 467:       {
 468:         // TODO: Is this 100% ok?
 469:         return true;
 470:       }
 471: 
 472:       /**
 473:        * Requests focus on the parent list. List children cannot request focus
 474:        * individually.
 475:        */
 476:       public void requestFocus()
 477:       {
 478:         // TODO: Is this 100% ok?
 479:         parent.requestFocus();
 480:       }
 481: 
 482:       /**
 483:        * Adds a focus listener to the parent list. List children do not have
 484:        * their own focus management.
 485:        *
 486:        * @param listener the focus listener to add
 487:        */
 488:       public void addFocusListener(FocusListener listener)
 489:       {
 490:         // TODO: Is this 100% ok?
 491:         parent.addFocusListener(listener);
 492:       }
 493: 
 494:       /**
 495:        * Removes a focus listener from the parent list. List children do not
 496:        * have their own focus management.
 497:        *
 498:        * @param listener the focus listener to remove
 499:        */
 500:       public void removeFocusListener(FocusListener listener)
 501:       {
 502:         // TODO: Is this 100%
 503:         parent.removeFocusListener(listener);
 504:       }
 505: 
 506:       /**
 507:        * Returns the accessible role of this list item, which is
 508:        * {@link AccessibleRole#LABEL}.
 509:        *
 510:        * @return {@link AccessibleRole#LABEL}
 511:        */
 512:       public AccessibleRole getAccessibleRole()
 513:       {
 514:         return AccessibleRole.LABEL;
 515:       }
 516: 
 517:       /**
 518:        * Returns the accessible state set of this list item.
 519:        *
 520:        * @return the accessible state set of this list item
 521:        */
 522:       public AccessibleStateSet getAccessibleStateSet()
 523:       {
 524:         AccessibleStateSet states = new AccessibleStateSet();
 525:         if (isVisible())
 526:           states.add(AccessibleState.VISIBLE);
 527:         if (isShowing())
 528:           states.add(AccessibleState.SHOWING);
 529:         if (isFocusTraversable())
 530:           states.add(AccessibleState.FOCUSABLE);
 531:         // TODO: How should the active state be handled? The API docs
 532:         // suggest that this state is set on the activated list child,
 533:         // that is the one that is drawn with a box. However, I don't know how
 534:         // to implement this.
 535: 
 536:         // TODO: We set the selectable state here because list children are
 537:         // selectable. Is there a way to disable single children?
 538:         if (parent.isEnabled())
 539:           states.add(AccessibleState.SELECTABLE);
 540:  
 541:         if (parent.isSelectedIndex(listIndex))
 542:           states.add(AccessibleState.SELECTED);
 543: 
 544:         // TODO: Handle more states here?
 545:         return states;
 546:       }
 547: 
 548:       /**
 549:        * Returns the index of this list child within it's parent list.
 550:        *
 551:        * @return the index of this list child within it's parent list
 552:        */
 553:       public int getAccessibleIndexInParent()
 554:       {
 555:         return listIndex;
 556:       }
 557: 
 558:       /**
 559:        * Returns <code>0</code> since list children don't have children
 560:        * themselves.
 561:        *
 562:        * @return <code>0</code>
 563:        */
 564:       public int getAccessibleChildrenCount()
 565:       {
 566:         return 0;
 567:       }
 568: 
 569:       /**
 570:        * Returns <code>null</code> since list children don't have children
 571:        * themselves.
 572:        *
 573:        * @return <code>null</code>
 574:        */
 575:       public Accessible getAccessibleChild(int i)
 576:       {
 577:         return null;
 578:       }
 579: 
 580:       /**
 581:        * Returns the locale of this component. This call is forwarded to the
 582:        * parent list since list children don't have a separate locale setting.
 583:        *
 584:        * @return the locale of this component
 585:        */
 586:       public Locale getLocale()
 587:       {
 588:         return parent.getLocale();
 589:       }
 590: 
 591:       /**
 592:        * This method does
 593:        * nothing, list children are transient accessible objects which means
 594:        * that they don't fire property change events.
 595:        *
 596:        * @param l not used here
 597:        */
 598:       public void addPropertyChangeListener(PropertyChangeListener l)
 599:       {
 600:         // Do nothing here.
 601:       }
 602: 
 603:       /**
 604:        * This method does
 605:        * nothing, list children are transient accessible objects which means
 606:        * that they don't fire property change events.
 607:        *
 608:        * @param l not used here
 609:        */
 610:       public void removePropertyChangeListener(PropertyChangeListener l)
 611:       {
 612:         // Do nothing here.
 613:       }
 614:       
 615:       // TODO: Implement the remaining methods of this class.
 616:     }
 617:     
 618:     /**
 619:      * Create a new AccessibleJList.
 620:      */
 621:     public AccessibleJList()
 622:     {
 623:       // Nothing to do here.
 624:     }
 625: 
 626:     /**
 627:      * Returns the number of selected accessible children.
 628:      *
 629:      * @return the number of selected accessible children
 630:      */
 631:     public int getAccessibleSelectionCount()
 632:     {
 633:       return getSelectedIndices().length;
 634:     }
 635: 
 636:     /**
 637:      * Returns the n-th selected accessible child.
 638:      *
 639:      * @param n the index of the selected child to return
 640:      *
 641:      * @return the n-th selected accessible child
 642:      */
 643:     public Accessible getAccessibleSelection(int n)
 644:     {
 645:       return new AccessibleJListChild(JList.this, getSelectedIndices()[n]);
 646:     }
 647: 
 648:     /**
 649:      * Returns <code>true</code> if the n-th child is selected,
 650:      * <code>false</code> otherwise.
 651:      *
 652:      * @param n the index of the child of which the selected state is queried
 653:      *
 654:      * @return <code>true</code> if the n-th child is selected,
 655:      *         <code>false</code> otherwise
 656:      */
 657:     public boolean isAccessibleChildSelected(int n)
 658:     {
 659:       return isSelectedIndex(n);
 660:     }
 661: 
 662:     /**
 663:      * Adds the accessible item with the specified index to the selected items.
 664:      * If multiple selections are supported, the item is added to the selection,
 665:      * otherwise the item replaces the current selection.
 666:      *
 667:      * @param i the index of the item to add to the selection
 668:      */
 669:     public void addAccessibleSelection(int i)
 670:     {
 671:       addSelectionInterval(i, i);
 672:     }
 673: 
 674:     /**
 675:      * Removes the accessible item with the specified index to the selection.
 676:      *
 677:      * @param i the index of the item to be removed from the selection
 678:      */
 679:     public void removeAccessibleSelection(int i)
 680:     {
 681:       removeSelectionInterval(i, i);
 682:     }
 683: 
 684:     /**
 685:      * Remove all selection items from the selection.
 686:      */
 687:     public void clearAccessibleSelection()
 688:     {
 689:       clearSelection();
 690:     }
 691: 
 692:     /**
 693:      * Selects all items if multiple selections are supported.
 694:      * Otherwise do nothing.
 695:      */
 696:     public void selectAllAccessibleSelection()
 697:     {
 698:       addSelectionInterval(0, getModel().getSize());
 699:     }
 700: 
 701:     /**
 702:      * Receices notification when the list selection is changed. This method
 703:      * fires two property change events, the first with
 704:      * {@link AccessibleContext#ACCESSIBLE_VISIBLE_DATA_PROPERTY} and the second
 705:      * with {@link AccessibleContext#ACCESSIBLE_SELECTION_PROPERTY}.
 706:      *
 707:      * @param event the list selection event
 708:      */
 709:     public void valueChanged(ListSelectionEvent event)
 710:     {
 711:       firePropertyChange(ACCESSIBLE_VISIBLE_DATA_PROPERTY, Boolean.FALSE,
 712:                          Boolean.TRUE);
 713:       firePropertyChange(ACCESSIBLE_SELECTION_PROPERTY, Boolean.FALSE,
 714:                          Boolean.TRUE);
 715:     }
 716: 
 717:     /**
 718:      * Receives notification when items have changed in the
 719:      * <code>JList</code>. This method fires a property change event with
 720:      * {@link AccessibleContext#ACCESSIBLE_VISIBLE_DATA_PROPERTY}.
 721:      *
 722:      * @param event the list data event
 723:      */
 724:     public void contentsChanged(ListDataEvent event)
 725:     {
 726:       firePropertyChange(ACCESSIBLE_VISIBLE_DATA_PROPERTY, Boolean.FALSE,
 727:                          Boolean.TRUE);
 728:     }
 729: 
 730:     /**
 731:      * Receives notification when items are inserted into the
 732:      * <code>JList</code>. This method fires a property change event with
 733:      * {@link AccessibleContext#ACCESSIBLE_VISIBLE_DATA_PROPERTY}.
 734:      *
 735:      * @param event the list data event
 736:      */
 737:     public void intervalAdded(ListDataEvent event)
 738:     {
 739:       firePropertyChange(ACCESSIBLE_VISIBLE_DATA_PROPERTY, Boolean.FALSE,
 740:                          Boolean.TRUE);
 741:     }
 742: 
 743:     /**
 744:      * Receives notification when items are removed from the
 745:      * <code>JList</code>. This method fires a property change event with
 746:      * {@link AccessibleContext#ACCESSIBLE_VISIBLE_DATA_PROPERTY}.
 747:      *
 748:      * @param event the list data event
 749:      */
 750:     public void intervalRemoved(ListDataEvent event)
 751:     {
 752:       firePropertyChange(ACCESSIBLE_VISIBLE_DATA_PROPERTY, Boolean.FALSE,
 753:                          Boolean.TRUE);
 754:     }
 755: 
 756: 
 757:     /**
 758:      * Receives notification about changes of the <code>JList</code>'s
 759:      * properties. This is used to re-register this object as listener to
 760:      * the data model and selection model when the data model or selection model
 761:      * changes.
 762:      *
 763:      * @param e the property change event
 764:      */
 765:     public void propertyChange(PropertyChangeEvent e)
 766:     {
 767:       String propertyName = e.getPropertyName();
 768:       if (propertyName.equals("model"))
 769:         {
 770:           ListModel oldModel = (ListModel) e.getOldValue();
 771:           oldModel.removeListDataListener(this);
 772:           ListModel newModel = (ListModel) e.getNewValue();
 773:           newModel.addListDataListener(this);
 774:         }
 775:       else if (propertyName.equals("selectionModel"))
 776:         {
 777:           ListSelectionModel oldModel = (ListSelectionModel) e.getOldValue();
 778:           oldModel.removeListSelectionListener(this);
 779:           ListSelectionModel newModel = (ListSelectionModel) e.getNewValue();
 780:           oldModel.addListSelectionListener(this);
 781:         }
 782:     }
 783: 
 784:     /**
 785:      * Return the state set of the <code>JList</code>.
 786:      *
 787:      * @return the state set of the <code>JList</code>
 788:      */
 789:     public AccessibleStateSet getAccessibleStateSet()
 790:     {
 791:       // TODO: Figure out if there is possibly more state that must be
 792:       // handled here.
 793:       AccessibleStateSet s = super.getAccessibleStateSet();
 794:       if (getSelectionMode() != ListSelectionModel.SINGLE_SELECTION)
 795:         s.add(AccessibleState.MULTISELECTABLE);
 796:       return s;
 797:     }
 798: 
 799:     /**
 800:      * Returns the accessible role for <code>JList</code>,
 801:      * {@link AccessibleRole#LIST}.
 802:      *
 803:      * @return the accessible role for <code>JList</code>
 804:      */
 805:     public AccessibleRole getAccessibleRole()
 806:     {
 807:       return AccessibleRole.LIST;
 808:     }
 809: 
 810:     /**
 811:      * Returns the accessible child at the visual location <code>p</code>
 812:      * (relative to the upper left corner of the <code>JList</code>). If there
 813:      * is no child at that location, this returns <code>null</code>.
 814:      *
 815:      * @param p the screen location for which to return the accessible child
 816:      *
 817:      * @return the accessible child at the specified location, or
 818:      *         <code>null</code> if there is no child at that location
 819:      */
 820:     public Accessible getAccessibleAt(Point p)
 821:     {
 822:       int childIndex = locationToIndex(p);
 823:       return getAccessibleChild(childIndex);
 824:     }
 825: 
 826:     /**
 827:      * Returns the number of accessible children in the <code>JList</code>.
 828:      *
 829:      * @return the number of accessible children in the <code>JList</code>
 830:      */
 831:     public int getAccessibleChildrenCount()
 832:     {
 833:       return getModel().getSize();
 834:     }
 835: 
 836:     /**
 837:      * Returns the n-th accessible child of this <code>JList</code>. This will
 838:      * be an instance of {@link AccessibleJListChild}. If there is no child
 839:      * at that index, <code>null</code> is returned.
 840:      *
 841:      * @param n the index of the child to return
 842:      *
 843:      * @return the n-th accessible child of this <code>JList</code>
 844:      */
 845:     public Accessible getAccessibleChild(int n)
 846:     {
 847:       if (getModel().getSize() <= n)
 848:         return null;
 849:       return new AccessibleJListChild(JList.this, n);
 850:     }
 851:   }
 852: 
 853:   private static final long serialVersionUID = 4406629526391098046L;
 854: 
 855:   /** 
 856:    * Constant value used in "layoutOrientation" property. This value means
 857:    * that cells are laid out in a single vertical column. This is the default. 
 858:    */
 859:   public static final int VERTICAL = 0;
 860: 
 861:   /** 
 862:    * Constant value used in "layoutOrientation" property. This value means
 863:    * that cells are laid out in multiple columns "newspaper style", filling
 864:    * vertically first, then horizontally. 
 865:    */
 866:   public static final int VERTICAL_WRAP = 1;
 867:   
 868:   /** 
 869:    * Constant value used in "layoutOrientation" property. This value means
 870:    * that cells are laid out in multiple columns "newspaper style",
 871:    * filling horizontally first, then vertically. 
 872:    */
 873:   public static final int HORIZONTAL_WRAP = 2;
 874: 
 875:   /**
 876:    * This property indicates whether "drag and drop" functions are enabled
 877:    * on the list.
 878:    */
 879:   boolean dragEnabled;
 880: 
 881:   /** This property provides a strategy for rendering cells in the list. */
 882:   ListCellRenderer cellRenderer;
 883: 
 884:   /**
 885:    * This property indicates an fixed width to assign to all cells in the
 886:    * list. If its value is <code>-1</code>, no width has been
 887:    * assigned. This value can be set explicitly, or implicitly by setting
 888:    * the {@link #prototypeCellValue} property.
 889:    */
 890:   int fixedCellWidth;
 891:   
 892:   /**
 893:    * This property indicates an fixed height to assign to all cells in the
 894:    * list. If its value is <code>-1</code>, no height has been
 895:    * assigned. This value can be set explicitly, or implicitly by setting
 896:    * the {@link #prototypeCellValue} property.
 897:    */
 898:   int fixedCellHeight;
 899: 
 900:   /** 
 901:    * This property holds the current layout orientation of the list, which
 902:    * is one of the integer constants {@link #VERTICAL}, {@link
 903:    * #VERTICAL_WRAP}, or {@link #HORIZONTAL_WRAP}. 
 904:    */
 905:   int layoutOrientation;
 906:   
 907:   /** This property holds the data elements displayed by the list. */
 908:   ListModel model;
 909: 
 910:   /**
 911:    * <p>This property holds a reference to a "prototype" data value --
 912:    * typically a String -- which is used to calculate the {@link
 913:    * #fixedCellWidth} and {@link #fixedCellHeight} properties, using the
 914:    * {@link #cellRenderer} property to acquire a component to render the
 915:    * prototype.</p>
 916:    *
 917:    * <p>It is important that you <em>not</em> set this value to a
 918:    * component. It has to be a <em>data value</em> such as the objects you
 919:    * would find in the list's model. Setting it to a component will have
 920:    * undefined (and undesirable) affects. </p>
 921:    */
 922:   Object prototypeCellValue;
 923: 
 924:   /** 
 925:    * This property specifies a foreground color for the selected cells in
 926:    * the list. When {@link ListCellRenderer#getListCellRendererComponent}
 927:    * is called with a selected cell object, the component returned will
 928:    * have its "foreground" set to this color.
 929:    */
 930:   Color selectionBackground;
 931: 
 932:   /** 
 933:    * This property specifies a background color for the selected cells in
 934:    * the list. When {@link ListCellRenderer#getListCellRendererComponent}
 935:    * is called with a selected cell object, the component returned will
 936:    * have its "background" property set to this color.
 937:    */
 938:   Color selectionForeground;
 939: 
 940:   /** 
 941:    * This property holds a description of which data elements in the {@link
 942:    * #model} property should be considered "selected", when displaying and
 943:    * interacting with the list.
 944:    */
 945:   ListSelectionModel selectionModel;
 946: 
 947: 
 948:   /**
 949:    * This property indicates that the list's selection is currently
 950:    * "adjusting" -- perhaps due to a user actively dragging the mouse over
 951:    * multiple list elements -- and is therefore likely to change again in
 952:    * the near future. A {@link ListSelectionListener} might choose to delay
 953:    * updating its view of the list's selection until this property is
 954:    * false, meaning that the adjustment has completed.
 955:    */
 956:   boolean valueIsAdjusting;
 957: 
 958:   /** 
 959:    * This property indicates a <em>preference</em> for the number of rows
 960:    * displayed in the list, and will scale the
 961:    * {@link #getPreferredScrollableViewportSize} property accordingly. The actual
 962:    * number of displayed rows, when the list is placed in a real {@link
 963:    * JViewport} or other component, may be greater or less than this number.
 964:    */
 965:   int visibleRowCount;
 966: 
 967:   /**
 968:    * Fire a {@link ListSelectionEvent} to all the registered 
 969:    * ListSelectionListeners.
 970:    * 
 971:    * @param firstIndex  the lowest index covering the selection change.
 972:    * @param lastIndex  the highest index covering the selection change.
 973:    * @param isAdjusting  a flag indicating if this event is one in a series
 974:    *     of events updating the selection.
 975:    */
 976:   protected void fireSelectionValueChanged(int firstIndex, int lastIndex, 
 977:                                            boolean isAdjusting) 
 978:   {
 979:     ListSelectionEvent evt = new ListSelectionEvent(this, firstIndex, 
 980:                                                     lastIndex, isAdjusting);
 981:     ListSelectionListener listeners[] = getListSelectionListeners();
 982:     for (int i = 0; i < listeners.length; ++i)
 983:       {
 984:         listeners[i].valueChanged(evt);
 985:       }
 986:   }
 987: 
 988:   /**
 989:    * This private listener propagates {@link ListSelectionEvent} events
 990:    * from the list's "selectionModel" property to the list's {@link
 991:    * ListSelectionListener} listeners. It also listens to {@link
 992:    * ListDataEvent} events from the list's {@link #model} property. If this
 993:    * class receives either type of event, it triggers repainting of the
 994:    * list.
 995:    */
 996:   private class ListListener 
 997:     implements ListSelectionListener, ListDataListener
 998:   {
 999:     // ListDataListener events
1000:     public void contentsChanged(ListDataEvent event)
1001:     {
1002:       JList.this.revalidate();
1003:       JList.this.repaint();
1004:     }
1005:     public void intervalAdded(ListDataEvent event)
1006:     {
1007:       JList.this.revalidate();
1008:       JList.this.repaint();
1009:     }
1010:     public void intervalRemoved(ListDataEvent event)
1011:     {
1012:       JList.this.revalidate();
1013:       JList.this.repaint();
1014:     }
1015:     // ListSelectionListener events
1016:     public void valueChanged(ListSelectionEvent event)
1017:     {
1018:       JList.this.fireSelectionValueChanged(event.getFirstIndex(),
1019:                                            event.getLastIndex(),
1020:                                            event.getValueIsAdjusting());
1021:       JList.this.repaint();
1022:     }
1023:   }
1024: 
1025:   /** 
1026:    * Shared ListListener instance, subscribed to both the current {@link
1027:    * #model} and {@link #selectionModel} properties of the list.
1028:    */
1029:   ListListener listListener;
1030: 
1031: 
1032:   /**
1033:    * Creates a new <code>JList</code> object.
1034:    */
1035:   public JList()
1036:   {
1037:     init(new DefaultListModel());
1038:   }
1039: 
1040:   /**
1041:    * Creates a new <code>JList</code> object.
1042:    *
1043:    * @param items  the initial list items.
1044:    */
1045:   public JList(Object[] items)
1046:   {
1047:     init(createListModel(items));
1048:   }
1049: 
1050:   /**
1051:    * Creates a new <code>JList</code> object.
1052:    *
1053:    * @param items  the initial list items.
1054:    */
1055:   public JList(Vector items)
1056:   {
1057:     init(createListModel(items));
1058:   }
1059: 
1060:   /**
1061:    * Creates a new <code>JList</code> object.
1062:    *
1063:    * @param model  a model containing the list items (<code>null</code> not
1064:    *     permitted).
1065:    *     
1066:    * @throws IllegalArgumentException if <code>model</code> is 
1067:    *     <code>null</code>.
1068:    */
1069:   public JList(ListModel model)
1070:   {
1071:     init(model);
1072:   }
1073: 
1074:   /**
1075:    * Initializes the list.
1076:    *
1077:    * @param m  the list model (<code>null</code> not permitted).
1078:    */
1079:   private void init(ListModel m)
1080:   {
1081:     if (m == null)
1082:       throw new IllegalArgumentException("Null model not permitted.");
1083:     dragEnabled = false;
1084:     fixedCellHeight = -1;
1085:     fixedCellWidth = -1;
1086:     layoutOrientation = VERTICAL;
1087:     opaque = true;
1088:     valueIsAdjusting = false;
1089:     visibleRowCount = 7;
1090: 
1091:     cellRenderer = new DefaultListCellRenderer();
1092:     listListener = new ListListener();
1093: 
1094:     model = m;
1095:     if (model != null)
1096:       model.addListDataListener(listListener);
1097: 
1098:     selectionModel = createSelectionModel();
1099:     if (selectionModel != null)
1100:       {
1101:         selectionModel.addListSelectionListener(listListener);
1102:         selectionModel.setSelectionMode
1103:                               (ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
1104:       }
1105:     setLayout(null);
1106:     
1107:     updateUI();
1108:   }
1109: 
1110:   /**
1111:    * Creates the default <code>ListSelectionModel</code>.
1112:    *
1113:    * @return the <code>ListSelectionModel</code>
1114:    */
1115:   protected ListSelectionModel createSelectionModel()
1116:   {
1117:     return new DefaultListSelectionModel();
1118:   }
1119:   
1120:   /**
1121:    * Gets the value of the {@link #fixedCellHeight} property. This property
1122:    * may be <code>-1</code> to indicate that no cell height has been
1123:    * set. This property is also set implicitly when the
1124:    * {@link #prototypeCellValue} property is set.
1125:    *
1126:    * @return The current value of the property 
1127:    * 
1128:    * @see #fixedCellHeight
1129:    * @see #setFixedCellHeight
1130:    * @see #setPrototypeCellValue
1131:    */
1132:   public int getFixedCellHeight()
1133:   {
1134:     return fixedCellHeight;
1135:   }
1136: 
1137:   /**
1138:    * Sets the value of the {@link #fixedCellHeight} property. This property
1139:    * may be <code>-1</code> to indicate that no cell height has been
1140:    * set. This property is also set implicitly when the {@link
1141:    * #prototypeCellValue} property is set, but setting it explicitly
1142:    * overrides the height computed from {@link #prototypeCellValue}.
1143:    *
1144:    * @param h  the height.
1145:    * 
1146:    * @see #getFixedCellHeight
1147:    * @see #getPrototypeCellValue
1148:    */
1149:   public void setFixedCellHeight(int h)
1150:   {
1151:     if (fixedCellHeight == h)
1152:       return;
1153: 
1154:     int old = fixedCellHeight;
1155:     fixedCellHeight = h;
1156:     firePropertyChange("fixedCellHeight", old, h);
1157:   }
1158: 
1159: 
1160:   /**
1161:    * Gets the value of the {@link #fixedCellWidth} property. This property
1162:    * may be <code>-1</code> to indicate that no cell width has been
1163:    * set. This property is also set implicitly when the {@link
1164:    * #prototypeCellValue} property is set.
1165:    *
1166:    * @return The current value of the property 
1167:    * 
1168:    * @see #setFixedCellWidth
1169:    * @see #setPrototypeCellValue
1170:    */
1171:   public int getFixedCellWidth()
1172:   {
1173:     return fixedCellWidth;
1174:   }
1175: 
1176:   /**
1177:    * Sets the value of the {@link #fixedCellWidth} property. This property
1178:    * may be <code>-1</code> to indicate that no cell width has been
1179:    * set. This property is also set implicitly when the {@link
1180:    * #prototypeCellValue} property is set, but setting it explicitly
1181:    * overrides the width computed from {@link #prototypeCellValue}.
1182:    *
1183:    * @param w  the width.
1184:    * 
1185:    * @see #getFixedCellHeight
1186:    * @see #getPrototypeCellValue
1187:    */
1188:   public void setFixedCellWidth(int w)
1189:   {
1190:     if (fixedCellWidth == w)
1191:       return;
1192:     
1193:     int old = fixedCellWidth;
1194:     fixedCellWidth = w;
1195:     firePropertyChange("fixedCellWidth", old, w);
1196:   }
1197: 
1198:   /** 
1199:    * Gets the value of the {@link #visibleRowCount} property. 
1200:    *
1201:    * @return the current value of the property.
1202:    */
1203: 
1204:   public int getVisibleRowCount()
1205:   {
1206:     return visibleRowCount;
1207:   }
1208: 
1209:   /**
1210:    * Sets the value of the {@link #visibleRowCount} property. 
1211:    *
1212:    * @param vc The new property value
1213:    */
1214:   public void setVisibleRowCount(int vc)
1215:   {
1216:     visibleRowCount = vc;
1217:     revalidate();
1218:     repaint();
1219:   }
1220: 
1221:   /**
1222:    * Adds a {@link ListSelectionListener} to the listener list for this
1223:    * list. The listener will be called back with a {@link
1224:    * ListSelectionEvent} any time the list's {@link #selectionModel}
1225:    * property changes. The source of such events will be the JList,
1226:    * not the selection model.
1227:    *
1228:    * @param listener The new listener to add
1229:    */
1230:   public void addListSelectionListener(ListSelectionListener listener)
1231:   {
1232:     listenerList.add (ListSelectionListener.class, listener);
1233:   }
1234: 
1235:   /**
1236:    * Removes a {@link ListSelectionListener} from the listener list for
1237:    * this list. The listener will no longer be called when the list's
1238:    * {@link #selectionModel} changes.
1239:    *
1240:    * @param listener The listener to remove
1241:    */
1242:   public void removeListSelectionListener(ListSelectionListener listener)
1243:   {
1244:     listenerList.remove(ListSelectionListener.class, listener);
1245:   }
1246: 
1247:   /**
1248:    * Returns an array of all ListSelectionListeners subscribed to this
1249:    * list. 
1250:    *
1251:    * @return The current subscribed listeners
1252:    *
1253:    * @since 1.4
1254:    */
1255:   public ListSelectionListener[] getListSelectionListeners()
1256:   {
1257:     return (ListSelectionListener[]) getListeners(ListSelectionListener.class);
1258:   }
1259: 
1260:   /**
1261:    * Returns the selection mode for the list (one of: 
1262:    * {@link ListSelectionModel#SINGLE_SELECTION}, 
1263:    * {@link ListSelectionModel#SINGLE_INTERVAL_SELECTION} and 
1264:    * {@link ListSelectionModel#MULTIPLE_INTERVAL_SELECTION}).
1265:    * 
1266:    * @return The selection mode.
1267:    * 
1268:    * @see #setSelectionMode(int)
1269:    */
1270:   public int getSelectionMode()
1271:   {
1272:     return selectionModel.getSelectionMode();
1273:   }
1274:   
1275:   /**
1276:    * Sets the list's "selectionMode" property, which simply mirrors the
1277:    * same property on the list's {@link #selectionModel} property. This
1278:    * property should be one of the integer constants
1279:    * <code>SINGLE_SELECTION</code>, <code>SINGLE_INTERVAL_SELECTION</code>,
1280:    * or <code>MULTIPLE_INTERVAL_SELECTION</code> from the {@link
1281:    * ListSelectionModel} interface.
1282:    *
1283:    * @param a The new selection mode
1284:    */
1285:   public void setSelectionMode(int a)
1286:   {
1287:     selectionModel.setSelectionMode(a);
1288:   }
1289: 
1290:   /**
1291:    * Adds the interval <code>[a,a]</code> to the set of selections managed
1292:    * by this list's {@link #selectionModel} property. Depending on the
1293:    * selection mode, this may cause existing selections to become invalid,
1294:    * or may simply expand the set of selections. 
1295:    *
1296:    * @param a A number in the half-open range <code>[0, x)</code> where
1297:    * <code>x = getModel.getSize()</code>, indicating the index of an
1298:    * element in the list to select. When &lt; 0 the selection is cleared.
1299:    *
1300:    * @see #setSelectionMode
1301:    * @see #selectionModel
1302:    */
1303:   public void setSelectedIndex(int a)
1304:   {
1305:     if (a < 0)
1306:       selectionModel.clearSelection();
1307:     else
1308:       selectionModel.setSelectionInterval(a, a);
1309:   }
1310: 
1311:   /**
1312:    * For each element <code>a[i]</code> of the provided array
1313:    * <code>a</code>, calls {@link #setSelectedIndex} on <code>a[i]</code>.
1314:    *
1315:    * @param a  an array of selected indices (<code>null</code> not permitted).
1316:    * 
1317:    * @throws NullPointerException if <code>a</code> is <code>null</code>.
1318:    * @see #setSelectionMode
1319:    * @see #selectionModel
1320:    */
1321:   public void setSelectedIndices(int [] a)
1322:   {
1323:     for (int i = 0; i < a.length; ++i)
1324:       setSelectedIndex(a[i]);
1325:   }
1326: 
1327:   /**
1328:    * Returns the minimum index of an element in the list which is currently
1329:    * selected.
1330:    *
1331:    * @return A number in the half-open range <code>[0, x)</code> where
1332:    * <code>x = getModel.getSize()</code>, indicating the minimum index of
1333:    * an element in the list for which the element is selected, or
1334:    * <code>-1</code> if no elements are selected
1335:    */
1336:   public int getSelectedIndex()
1337:   {
1338:     return selectionModel.getMinSelectionIndex();
1339:   }
1340: 
1341:   /**
1342:    * Returns <code>true</code> if the model's selection is empty, otherwise
1343:    * <code>false</code>. 
1344:    *
1345:    * @return The return value of {@link ListSelectionModel#isSelectionEmpty}
1346:    */
1347:   public boolean isSelectionEmpty()
1348:   {
1349:     return selectionModel.isSelectionEmpty();
1350:   }
1351: 
1352:   /**
1353:    * Returns the list index of the upper left or upper right corner of the
1354:    * visible rectangle of this list, depending on the {@link
1355:    * Component#getComponentOrientation} property.
1356:    *
1357:    * @return The index of the first visible list cell, or <code>-1</code>
1358:    * if none is visible.
1359:    */
1360:   public int getFirstVisibleIndex()
1361:   {
1362:     ComponentOrientation or = getComponentOrientation();
1363:     Rectangle r = getVisibleRect();
1364:     if (or == ComponentOrientation.RIGHT_TO_LEFT)
1365:       r.translate((int) r.getWidth() - 1, 0);
1366:     return getUI().locationToIndex(this, r.getLocation());      
1367:   }
1368: 
1369: 
1370:   /**
1371:    * Returns index of the cell to which specified location is closest to. If
1372:    * the location is outside the bounds of the list, then the greatest index
1373:    * in the list model is returned. If the list model is empty, then
1374:    * <code>-1</code> is returned.
1375:    *
1376:    * @param location for which to look for in the list
1377:    * 
1378:    * @return index of the cell to which specified location is closest to.
1379:    */
1380:    public int locationToIndex(Point location)
1381:    {
1382:      return getUI().locationToIndex(this, location);      
1383:    }
1384: 
1385:   /**
1386:    * Returns location of the cell located at the specified index in the list.
1387:    * @param index of the cell for which location will be determined
1388:    * 
1389:    * @return location of the cell located at the specified index in the list.
1390:    */
1391:    public Point indexToLocation(int index)
1392:    {
1393:      return getUI().indexToLocation(this, index);
1394:    }
1395: 
1396:   /**
1397:    * Returns the list index of the lower right or lower left corner of the
1398:    * visible rectangle of this list, depending on the {@link
1399:    * Component#getComponentOrientation} property.
1400:    *
1401:    * @return The index of the last visible list cell, or <code>-1</code>
1402:    * if none is visible.
1403:    */
1404:   public int getLastVisibleIndex()
1405:   {
1406:     ComponentOrientation or = getComponentOrientation();
1407:     Rectangle r = getVisibleRect();
1408:     r.translate(0, (int) r.getHeight() - 1);
1409:     if (or == ComponentOrientation.LEFT_TO_RIGHT)
1410:       r.translate((int) r.getWidth() - 1, 0);
1411:     if (getUI().locationToIndex(this, r.getLocation()) == -1
1412:         && indexToLocation(getModel().getSize() - 1).y < r.y)
1413:       return getModel().getSize() - 1;
1414:     return getUI().locationToIndex(this, r.getLocation());
1415:   }
1416: 
1417:   /**
1418:    * Returns the indices of values in the {@link #model} property which are
1419:    * selected.
1420:    *
1421:    * @return An array of model indices, each of which is selected according
1422:    *         to the {@link #getSelectedValues} property
1423:    */
1424:   public int[] getSelectedIndices()
1425:   {
1426:     int lo, hi, n, i, j;
1427:     if (selectionModel.isSelectionEmpty())
1428:       return new int[0];
1429:     lo = selectionModel.getMinSelectionIndex();
1430:     hi = selectionModel.getMaxSelectionIndex();
1431:     n = 0;
1432:     for (i = lo; i <= hi; ++i)
1433:       if (selectionModel.isSelectedIndex(i))
1434:         n++;
1435:     int [] v = new int[n];
1436:     j = 0;
1437:     for (i = lo; i <= hi; ++i)
1438:       if (selectionModel.isSelectedIndex(i))
1439:         v[j++] = i;
1440:     return v;
1441:   }
1442: 
1443:   /**
1444:    * Indicates whether the list element at a given index value is
1445:    * currently selected.
1446:    *
1447:    * @param a The index to check 
1448:    * @return <code>true</code> if <code>a</code> is the index of a selected
1449:    * list element
1450:    */
1451:   public boolean isSelectedIndex(int a)
1452:   {
1453:     return selectionModel.isSelectedIndex(a);
1454:   }
1455: 
1456:   /**
1457:    * Returns the first value in the list's {@link #model} property which is
1458:    * selected, according to the list's {@link #selectionModel} property.
1459:    * This is equivalent to calling
1460:    * <code>getModel()getElementAt(getSelectedIndex())</code>, with a check
1461:    * for the special index value of <code>-1</code> which returns null
1462:    * <code>null</code>.
1463:    *
1464:    * @return The first selected element, or <code>null</code> if no element
1465:    * is selected.
1466:    *
1467:    * @see #getSelectedValues
1468:    */
1469:   public Object getSelectedValue()
1470:   {
1471:     int index = getSelectedIndex();
1472:     if (index == -1)
1473:       return null;
1474:     return getModel().getElementAt(index);
1475:   }
1476: 
1477:   /**
1478:    * Returns all the values in the list's {@link #model} property which are
1479:    * selected, according to the list's {@link #selectionModel} property.
1480:    * 
1481:    * @return An array containing all the selected values
1482:    * @see #setSelectedValue
1483:    */
1484:   public Object[] getSelectedValues()
1485:   {
1486:     int[] idx = getSelectedIndices();
1487:     Object[] v = new Object[idx.length];
1488:     for (int i = 0; i < idx.length; ++i)
1489:       v[i] = getModel().getElementAt(idx[i]);
1490:     return v;
1491:   }
1492: 
1493:   /**
1494:    * Gets the value of the {@link #selectionBackground} property.
1495:    *
1496:    * @return The current value of the property
1497:    */
1498:   public Color getSelectionBackground()
1499:   {
1500:     return selectionBackground;
1501:   }
1502: 
1503:   /**
1504:    * Sets the value of the {@link #selectionBackground} property.
1505:    *
1506:    * @param c The new value of the property
1507:    */
1508:   public void setSelectionBackground(Color c)
1509:   {
1510:     if (selectionBackground == c)
1511:       return;
1512: 
1513:     Color old = selectionBackground;
1514:     selectionBackground = c;
1515:     firePropertyChange("selectionBackground", old, c);
1516:     repaint();
1517:   }
1518: 
1519:   /**
1520:    * Gets the value of the {@link #selectionForeground} property.
1521:    *
1522:    * @return The current value of the property
1523:    */
1524:   public Color getSelectionForeground()
1525:   {
1526:     return selectionForeground;
1527:   }
1528:   
1529:   /**
1530:    * Sets the value of the {@link #selectionForeground} property.
1531:    *
1532:    * @param c The new value of the property
1533:    */
1534:   public void setSelectionForeground(Color c)
1535:   {
1536:     if (selectionForeground == c)
1537:       return;
1538: 
1539:     Color old = selectionForeground;
1540:     selectionForeground = c;
1541:     firePropertyChange("selectionForeground", old, c);
1542:   }
1543: 
1544:   /**
1545:    * Sets the selection to cover only the specified value, if it
1546:    * exists in the model. 
1547:    *
1548:    * @param obj The object to select
1549:    * @param scroll Whether to scroll the list to make the newly selected
1550:    * value visible
1551:    *
1552:    * @see #ensureIndexIsVisible
1553:    */
1554: 
1555:   public void setSelectedValue(Object obj, boolean scroll)
1556:   {
1557:     for (int i = 0; i < model.getSize(); ++i)
1558:       {
1559:         if (model.getElementAt(i).equals(obj))
1560:           {
1561:             setSelectedIndex(i);
1562:             if (scroll)
1563:               ensureIndexIsVisible(i);
1564:             break;
1565:           }
1566:       }
1567:   }
1568: 
1569:   /**
1570:    * Scrolls this list to make the specified cell visible. This
1571:    * only works if the list is contained within a viewport.
1572:    *
1573:    * @param i The list index to make visible
1574:    *
1575:    * @see JComponent#scrollRectToVisible
1576:    */
1577:   public void ensureIndexIsVisible(int i)
1578:   {
1579:     Rectangle r = getUI().getCellBounds(this, i, i);
1580:     if (r != null)
1581:       scrollRectToVisible(r);
1582:   }
1583: 
1584:   /**
1585:    * Sets the {@link #model} property of the list to a new anonymous
1586:    * {@link AbstractListModel} subclass which accesses the provided Object
1587:    * array directly.
1588:    *
1589:    * @param listData The object array to build a new list model on
1590:    * @see #setModel
1591:    */
1592:   public void setListData(Object[] listData)
1593:   {
1594:     setModel(createListModel(listData));
1595:   }
1596: 
1597:   /**
1598:    * Returns a {@link ListModel} backed by the specified array.
1599:    * 
1600:    * @param items  the list items (don't use <code>null</code>).
1601:    * 
1602:    * @return A list model containing the specified items.
1603:    */
1604:   private ListModel createListModel(final Object[] items)
1605:   {
1606:     return new AbstractListModel()
1607:       {
1608:         public int getSize()
1609:         {
1610:           return items.length;
1611:         }
1612:         public Object getElementAt(int i)
1613:         {
1614:           return items[i];
1615:         }
1616:       };
1617:   }
1618:   
1619:   /**
1620:    * Returns a {@link ListModel} backed by the specified vector.
1621:    * 
1622:    * @param items  the list items (don't use <code>null</code>).
1623:    * 
1624:    * @return A list model containing the specified items.
1625:    */
1626:   private ListModel createListModel(final Vector items)
1627:   {
1628:     return new AbstractListModel()
1629:       {
1630:         public int getSize()
1631:         {
1632:           return items.size();
1633:         }
1634:         public Object getElementAt(int i)
1635:         {
1636:           return items.get(i);
1637:         }
1638:       };
1639:   }
1640: 
1641:   /**
1642:    * Sets the {@link #model} property of the list to a new anonymous {@link
1643:    * AbstractListModel} subclass which accesses the provided vector
1644:    * directly.
1645:    *
1646:    * @param listData The object array to build a new list model on
1647:    * @see #setModel
1648:    */
1649:   public void setListData(Vector listData)
1650:   {
1651:     setModel(createListModel(listData));
1652:   }
1653: 
1654:   /**
1655:    * Gets the value of the {@link #cellRenderer} property. 
1656:    *
1657:    * @return The current value of the property
1658:    */
1659:   public ListCellRenderer getCellRenderer()
1660:   {
1661:     return cellRenderer;
1662:   }
1663: 
1664:   /**
1665:    * Sets the value of the {@link #getCellRenderer} property.
1666:    *
1667:    * @param renderer The new property value
1668:    */
1669:   public void setCellRenderer(ListCellRenderer renderer)
1670:   {
1671:     if (cellRenderer == renderer)
1672:       return;
1673:     
1674:     ListCellRenderer old = cellRenderer;
1675:     cellRenderer = renderer;
1676:     firePropertyChange("cellRenderer", old, renderer);
1677:     revalidate();
1678:     repaint();
1679:   }
1680: 
1681:   /**
1682:    * Gets the value of the {@link #model} property. 
1683:    *
1684:    * @return The current value of the property
1685:    */
1686:   public ListModel getModel()
1687:   {
1688:     return model;
1689:   }
1690: 
1691:   /**
1692:    * Sets the value of the {@link #model} property. The list's {@link
1693:    * #listListener} is unsubscribed from the existing model, if it exists,
1694:    * and re-subscribed to the new model.
1695:    *
1696:    * @param model  the new model (<code>null</code> not permitted).
1697:    * 
1698:    * @throws IllegalArgumentException if <code>model</code> is 
1699:    *         <code>null</code>.
1700:    */
1701:   public void setModel(ListModel model)
1702:   {
1703:     if (model == null) 
1704:       throw new IllegalArgumentException("Null 'model' argument.");
1705:     if (this.model == model)
1706:       return;
1707:     
1708:     if (this.model != null)
1709:       this.model.removeListDataListener(listListener);
1710:     
1711:     ListModel old = this.model;
1712:     this.model = model;
1713:     
1714:     if (this.model != null)
1715:       this.model.addListDataListener(listListener);
1716:     
1717:     firePropertyChange("model", old, model);
1718:     revalidate();
1719:     repaint();
1720:   }
1721: 
1722:   /**
1723:    * Returns the selection model for the {@link JList} component.  Note that
1724:    * this class contains a range of convenience methods for configuring the
1725:    * selection model:<br>
1726:    * <ul>
1727:    *   <li>{@link #clearSelection()};</li>
1728:    *   <li>{@link #setSelectionMode(int)};</li>
1729:    *   <li>{@link #addSelectionInterval(int, int)};</li>
1730:    *   <li>{@link #setSelectedIndex(int)};</li>
1731:    *   <li>{@link #setSelectedIndices(int[])};</li>
1732:    *   <li>{@link #setSelectionInterval(int, int)}.</li>
1733:    * </ul>
1734:    * 
1735:    * @return The selection model.
1736:    */
1737:   public ListSelectionModel getSelectionModel()
1738:   {
1739:     return selectionModel;
1740:   }
1741: 
1742:   /**
1743:    * Sets the value of the {@link #selectionModel} property. The list's
1744:    * {@link #listListener} is unsubscribed from the existing selection
1745:    * model, if it exists, and re-subscribed to the new selection model.
1746:    *
1747:    * @param model The new property value
1748:    */
1749:   public void setSelectionModel(ListSelectionModel model)
1750:   {
1751:     if (selectionModel == model)
1752:       return;
1753:     
1754:     if (selectionModel != null)
1755:       selectionModel.removeListSelectionListener(listListener);
1756:     
1757:     ListSelectionModel old = selectionModel;
1758:     selectionModel = model;
1759:     
1760:     if (selectionModel != null)
1761:       selectionModel.addListSelectionListener(listListener);
1762:     
1763:     firePropertyChange("selectionModel", old, model);
1764:     revalidate();
1765:     repaint();
1766:   }
1767: 
1768:   /**
1769:    * Gets the value of the UI property.
1770:    *
1771:    * @return The current property value
1772:    */
1773:   public ListUI getUI()
1774:   {
1775:     return (ListUI) ui;
1776:   }
1777: 
1778:   /**
1779:    * Sets the value of the UI property.
1780:    *
1781:    * @param ui The new property value
1782:    */
1783:   public void setUI(ListUI ui)
1784:   {
1785:     super.setUI(ui);
1786:   }
1787: 
1788:   /**
1789:    * Calls {@link #setUI} with the {@link ListUI} subclass
1790:    * returned from calling {@link UIManager#getUI}.
1791:    */
1792:   public void updateUI()
1793:   {
1794:     setUI((ListUI) UIManager.getUI(this));
1795:   }
1796: 
1797:   /**
1798:    * Return the class identifier for the list's UI property.  This should
1799:    * be the constant string <code>"ListUI"</code>, and map to an
1800:    * appropriate UI class in the {@link UIManager}.
1801:    *
1802:    * @return The class identifier
1803:    */
1804:   public String getUIClassID()
1805:   {
1806:     return "ListUI";
1807:   }
1808: 
1809: 
1810:   /**
1811:    * Returns the current value of the {@link #prototypeCellValue}
1812:    * property. This property holds a reference to a "prototype" data value
1813:    * -- typically a String -- which is used to calculate the {@link
1814:    * #fixedCellWidth} and {@link #fixedCellHeight} properties, using the
1815:    * {@link #cellRenderer} property to acquire a component to render the
1816:    * prototype.
1817:    *
1818:    * @return The current prototype cell value
1819:    * @see #setPrototypeCellValue
1820:    */
1821:   public Object getPrototypeCellValue()
1822:   {
1823:     return prototypeCellValue;
1824:   }
1825: 
1826:   /**
1827:    * <p>Set the {@link #prototypeCellValue} property. This property holds a
1828:    * reference to a "prototype" data value -- typically a String -- which
1829:    * is used to calculate the {@link #fixedCellWidth} and {@link
1830:    * #fixedCellHeight} properties, using the {@link #cellRenderer} property
1831:    * to acquire a component to render the prototype.</p>
1832:    *
1833:    * <p>It is important that you <em>not</em> set this value to a
1834:    * component. It has to be a <em>data value</em> such as the objects you
1835:    * would find in the list's model. Setting it to a component will have
1836:    * undefined (and undesirable) affects. </p>
1837:    *
1838:    * @param obj The new prototype cell value
1839:    * @see #getPrototypeCellValue
1840:    */
1841:   public void setPrototypeCellValue(Object obj)
1842:   {
1843:     if (prototypeCellValue == obj)
1844:       return;
1845: 
1846:     Object old = prototypeCellValue;
1847:     Component comp = getCellRenderer()
1848:       .getListCellRendererComponent(this, obj, 0, false, false); 
1849:     Dimension d = comp.getPreferredSize();
1850:     fixedCellWidth = d.width;
1851:     fixedCellHeight = d.height;
1852:     prototypeCellValue = obj;
1853:     firePropertyChange("prototypeCellValue", old, obj);
1854:   }
1855: 
1856:   public AccessibleContext getAccessibleContext()
1857:   {
1858:     return new AccessibleJList();
1859:   }
1860: 
1861:   /**
1862:    * Returns a size indicating how much space this list would like to
1863:    * consume, when contained in a scrollable viewport. This is part of the
1864:    * {@link Scrollable} interface, which interacts with {@link
1865:    * ScrollPaneLayout} and {@link JViewport} to define scrollable objects.
1866:    *
1867:    * @return The preferred size
1868:    */
1869:   public Dimension getPreferredScrollableViewportSize()
1870:   {
1871:     //If the layout orientation is not VERTICAL, then this will 
1872:     //return the value from getPreferredSize. The current ListUI is 
1873:     //expected to override getPreferredSize to return an appropriate value.
1874:     if (getLayoutOrientation() != VERTICAL)
1875:       return getPreferredSize();        
1876: 
1877:     int size = getModel().getSize();
1878:     
1879:     // Trivial case: if fixedCellWidth and fixedCellHeight were set 
1880:     // just use them
1881:     if (fixedCellHeight != -1 && fixedCellWidth != -1)
1882:       return new Dimension(fixedCellWidth, size * fixedCellHeight);
1883:         
1884:     // If the model is empty we use 16 * the number of visible rows
1885:     // for the height and either fixedCellWidth (if set) or 256
1886:     // for the width
1887:     if (size == 0)
1888:       {
1889:         if (fixedCellWidth == -1)
1890:           return new Dimension(256, 16 * getVisibleRowCount());
1891:         else
1892:           return new Dimension(fixedCellWidth, 16 * getVisibleRowCount());
1893:       }
1894: 
1895:     // Calculate the width: if fixedCellWidth was set use that, otherwise
1896:     // use the preferredWidth
1897:     int prefWidth;
1898:     if (fixedCellWidth != -1)
1899:       prefWidth = fixedCellWidth;
1900:     else
1901:       prefWidth = getPreferredSize().width;
1902: 
1903:     // Calculate the height: if fixedCellHeight was set use that, otherwise
1904:     // use the height of the first row multiplied by the number of visible
1905:     // rows
1906:     int prefHeight;
1907:     if (fixedCellHeight != -1)
1908:       prefHeight = fixedCellHeight;
1909:     else
1910:       prefHeight = getVisibleRowCount() * getCellBounds(0, 0).height;
1911: 
1912:     return new Dimension (prefWidth, prefHeight);
1913:   }
1914: 
1915:   /**
1916:    * <p>Return the number of pixels the list must scroll in order to move a
1917:    * "unit" of the list into the provided visible rectangle. When the
1918:    * provided direction is positive, the call describes a "downwards"
1919:    * scroll, which will be exposing a cell at a <em>greater</em> index in
1920:    * the list than those elements currently showing. Then the provided
1921:    * direction is negative, the call describes an "upwards" scroll, which
1922:    * will be exposing a cell at a <em>lesser</em> index in the list than
1923:    * those elements currently showing.</p>
1924:    *
1925:    * <p>If the provided orientation is <code>HORIZONTAL</code>, the above
1926:    * comments refer to "rightwards" for positive direction, and "leftwards"
1927:    * for negative.</p>
1928:    * 
1929:    *
1930:    * @param visibleRect The rectangle to scroll an element into
1931:    * @param orientation One of the numeric consants <code>VERTICAL</code>
1932:    * or <code>HORIZONTAL</code>
1933:    * @param direction An integer indicating the scroll direction: positive means
1934:    * forwards (down, right), negative means backwards (up, left)
1935:    *
1936:    * @return The scrollable unit increment, in pixels
1937:    */
1938:   public int getScrollableUnitIncrement(Rectangle visibleRect,
1939:                                         int orientation, int direction)
1940:   {
1941:     ListUI lui = this.getUI();
1942:     if (orientation == SwingConstants.VERTICAL)
1943:       {
1944:         if (direction > 0)
1945:           {
1946:             // Scrolling down
1947:             Point bottomLeft = new Point(visibleRect.x,
1948:                                          visibleRect.y + visibleRect.height);
1949:             int curIdx = lui.locationToIndex(this, bottomLeft);
1950:             Rectangle curBounds = lui.getCellBounds(this, curIdx, curIdx);
1951:             if (curBounds.y + curBounds.height == bottomLeft.y)
1952:               {
1953:                 // we are at the exact bottom of the current cell, so we 
1954:                 // are being asked to scroll to the end of the next one
1955:                 if (curIdx + 1 < model.getSize())
1956:                   {
1957:                     // there *is* a next item in the list
1958:                     Rectangle nxtBounds = lui.getCellBounds(this, curIdx + 1, curIdx + 1);
1959:                     return nxtBounds.height;
1960:                   }
1961:                 else
1962:                   {
1963:                     // no next item, no advance possible
1964:                     return 0;
1965:                   }
1966:               }
1967:             else
1968:               {
1969:                 // we are part way through an existing cell, so we are being
1970:                 // asked to scroll to the bottom of it
1971:                 return (curBounds.y + curBounds.height) - bottomLeft.y;
1972:               }              
1973:           }
1974:         else
1975:           {
1976:             // scrolling up
1977:             Point topLeft = new Point(visibleRect.x, visibleRect.y);
1978:             int curIdx = lui.locationToIndex(this, topLeft);
1979:             Rectangle curBounds = lui.getCellBounds(this, curIdx, curIdx);
1980:             if (curBounds.y == topLeft.y)
1981:               {
1982:                 // we are at the exact top of the current cell, so we 
1983:                 // are being asked to scroll to the top of the previous one
1984:                 if (curIdx > 0)
1985:                   {
1986:                     // there *is* a previous item in the list
1987:                     Rectangle nxtBounds = lui.getCellBounds(this, curIdx - 1, curIdx - 1);
1988:                     return -nxtBounds.height;
1989:                   }
1990:                 else
1991:                   {
1992:                     // no previous item, no advance possible
1993:                     return 0;
1994:                   }
1995:               }
1996:             else
1997:               {
1998:                 // we are part way through an existing cell, so we are being
1999:                 // asked to scroll to the top of it
2000:                 return curBounds.y - topLeft.y;
2001:               }              
2002:           }
2003:       }
2004: 
2005:     // FIXME: handle horizontal scrolling (also wrapping?)
2006:     return 1;
2007:   }
2008: 
2009:   /**
2010:    * <p>Return the number of pixels the list must scroll in order to move a
2011:    * "block" of the list into the provided visible rectangle. When the
2012:    * provided direction is positive, the call describes a "downwards"
2013:    * scroll, which will be exposing a cell at a <em>greater</em> index in
2014:    * the list than those elements currently showing. Then the provided
2015:    * direction is negative, the call describes an "upwards" scroll, which
2016:    * will be exposing a cell at a <em>lesser</em> index in the list than
2017:    * those elements currently showing.</p>
2018:    *
2019:    * <p>If the provided orientation is <code>HORIZONTAL</code>, the above
2020:    * comments refer to "rightwards" for positive direction, and "leftwards"
2021:    * for negative.</p>
2022:    * 
2023:    *
2024:    * @param visibleRect The rectangle to scroll an element into
2025:    * @param orientation One of the numeric consants <code>VERTICAL</code>
2026:    * or <code>HORIZONTAL</code>
2027:    * @param direction An integer indicating the scroll direction: positive means
2028:    * forwards (down, right), negative means backwards (up, left)
2029:    *
2030:    * @return The scrollable unit increment, in pixels
2031:    */
2032:   public int getScrollableBlockIncrement(Rectangle visibleRect,
2033:                                          int orientation, int direction)
2034:   {
2035:       if (orientation == VERTICAL)
2036:       return visibleRect.height * direction;
2037:       else
2038:       return visibleRect.width * direction;
2039:   }
2040: 
2041:   /**
2042:    * Gets the value of the <code>scrollableTracksViewportWidth</code> property.
2043:    *
2044:    * @return <code>true</code> if the viewport is larger (horizontally)
2045:    * than the list and the list should be expanded to fit the viewport;
2046:    * <code>false</code> if the viewport is smaller than the list and the
2047:    * list should scroll (horizontally) within the viewport
2048:    */
2049:   public boolean getScrollableTracksViewportWidth()
2050:   {
2051:     Component parent = getParent();
2052:     boolean retVal = false;
2053:     if (parent instanceof JViewport)
2054:       {
2055:         JViewport viewport = (JViewport) parent;
2056:         Dimension pref = getPreferredSize();
2057:         if (viewport.getSize().width > pref.width)
2058:           retVal = true;
2059:         if ((getLayoutOrientation() == HORIZONTAL_WRAP)
2060:             && (getVisibleRowCount() <= 0))
2061:           retVal = true;
2062:       }
2063:     return retVal;
2064:   }
2065: 
2066:   /**
2067:    * Gets the value of the </code>scrollableTracksViewportWidth</code> property.
2068:    *
2069:    * @return <code>true</code> if the viewport is larger (vertically)
2070:    * than the list and the list should be expanded to fit the viewport;
2071:    * <code>false</code> if the viewport is smaller than the list and the
2072:    * list should scroll (vertically) within the viewport
2073:    */
2074:   public boolean getScrollableTracksViewportHeight()
2075:   {
2076:     Component parent = getParent();
2077:     boolean retVal = false;
2078:     if (parent instanceof JViewport)
2079:       {
2080:         JViewport viewport = (JViewport) parent;
2081:         Dimension pref = getPreferredSize();
2082:         if (viewport.getSize().height > pref.height)
2083:           retVal = true;
2084:         if ((getLayoutOrientation() == VERTICAL_WRAP)
2085:             && (getVisibleRowCount() <= 0))
2086:           retVal = true;
2087:       }
2088:     return retVal;
2089:   }
2090: 
2091:   /**
2092:    * Returns the index of the anchor item in the current selection, or
2093:    * <code>-1</code> if there is no anchor item.
2094:    * 
2095:    * @return The item index.
2096:    */
2097:   public int getAnchorSelectionIndex()
2098:   {
2099:     return selectionModel.getAnchorSelectionIndex();
2100:   }
2101: 
2102:   /**
2103:    * Returns the index of the lead item in the current selection, or
2104:    * <code>-1</code> if there is no lead item.
2105:    * 
2106:    * @return The item index.
2107:    */
2108:   public int getLeadSelectionIndex()
2109:   {
2110:     return selectionModel.getLeadSelectionIndex();
2111:   }
2112: 
2113:   /**
2114:    * Returns the lowest item index in the current selection, or <code>-1</code>
2115:    * if there is no selection.
2116:    * 
2117:    * @return The index.
2118:    * 
2119:    * @see #getMaxSelectionIndex()
2120:    */
2121:   public int getMinSelectionIndex()
2122:   {
2123:     return selectionModel.getMinSelectionIndex();
2124:   }
2125: 
2126:   /**
2127:    * Returns the highest item index in the current selection, or 
2128:    * <code>-1</code> if there is no selection.
2129:    * 
2130:    * @return The index.
2131:    * 
2132:    * @see #getMinSelectionIndex()
2133:    */
2134:   public int getMaxSelectionIndex()
2135:   {
2136:     return selectionModel.getMaxSelectionIndex();
2137:   }
2138: 
2139:   /**
2140:    * Clears the current selection.
2141:    */
2142:   public void clearSelection()
2143:   {
2144:     selectionModel.clearSelection();
2145:   }
2146: 
2147:   /**
2148:    * Sets the current selection to the items in the specified range (inclusive).
2149:    * Note that <code>anchor</code> can be less than, equal to, or greater than 
2150:    * <code>lead</code>.
2151:    * 
2152:    * @param anchor  the index of the anchor item.
2153:    * @param lead  the index of the anchor item.
2154:    */
2155:   public void setSelectionInterval(int anchor, int lead)
2156:   {
2157:     selectionModel.setSelectionInterval(anchor, lead);
2158:   }
2159: 
2160:   /**
2161:    * Adds the specified interval to the current selection.  Note that 
2162:    * <code>anchor</code> can be less than, equal to, or greater than 
2163:    * <code>lead</code>.
2164:    * 
2165:    * @param anchor  the index of the anchor item.
2166:    * @param lead  the index of the lead item.
2167:    */
2168:   public void addSelectionInterval(int anchor, int lead)
2169:   {
2170:     selectionModel.addSelectionInterval(anchor, lead);
2171:   }
2172: 
2173:   /**
2174:    * Removes the specified interval from the current selection.  Note that 
2175:    * <code>index0</code> can be less than, equal to, or greater than 
2176:    * <code>index1</code>.
2177:    * 
2178:    * @param index0  an index for one end of the range.
2179:    * @param index1  an index for the other end of the range.
2180:    */
2181:   public void removeSelectionInterval(int index0, int index1)
2182:   {
2183:     selectionModel.removeSelectionInterval(index0, index1);
2184:   }
2185: 
2186:   /**
2187:    * Returns the value of the <code>valueIsAdjusting</code> property.
2188:    *
2189:    * @return the value
2190:    */
2191:   public boolean getValueIsAdjusting()
2192:   {
2193:     return valueIsAdjusting;
2194:   }
2195: 
2196:   /**
2197:    * Sets the <code>valueIsAdjusting</code> property.
2198:    *
2199:    * @param isAdjusting the new value
2200:    */
2201:   public void setValueIsAdjusting(boolean isAdjusting)
2202:   {
2203:     valueIsAdjusting = isAdjusting;
2204:   }
2205: 
2206:   /**
2207:    * Return the value of the <code>dragEnabled</code> property.
2208:    *
2209:    * @return the value
2210:    * 
2211:    * @since 1.4
2212:    */
2213:   public boolean getDragEnabled()
2214:   {
2215:     return dragEnabled;
2216:   }
2217: 
2218:   /**
2219:    * Set the <code>dragEnabled</code> property.
2220:    *
2221:    * @param enabled new value
2222:    * 
2223:    * @since 1.4
2224:    */
2225:   public void setDragEnabled(boolean enabled)
2226:   {
2227:     dragEnabled = enabled;
2228:   }
2229: 
2230:   /**
2231:    * Returns the layout orientation.
2232:    *
2233:    * @return the orientation, one of <code>JList.VERTICAL</code>,
2234:    * <code>JList.VERTICAL_WRAP</code> and <code>JList.HORIZONTAL_WRAP</code>
2235:    *
2236:    * @since 1.4
2237:    */
2238:   public int getLayoutOrientation()
2239:   {
2240:     return layoutOrientation;
2241:   }
2242: 
2243:   /**
2244:    * Sets the layout orientation.
2245:    *
2246:    * @param orientation the orientation to set, one of <code>JList.VERTICAL</code>,
2247:    * <code>JList.VERTICAL_WRAP</code> and <code>JList.HORIZONTAL_WRAP</code>
2248:    *
2249:    * @since 1.4
2250:    */
2251:   public void setLayoutOrientation(int orientation)
2252:   {
2253:     if (layoutOrientation == orientation)
2254:       return;
2255: 
2256:     int old = layoutOrientation;
2257:     layoutOrientation = orientation;
2258:     firePropertyChange("layoutOrientation", old, orientation);
2259:   }
2260: 
2261:   /**
2262:    * Returns the bounds of the rectangle that encloses both list cells
2263:    * with index0 and index1.
2264:    *
2265:    * @param index0 the index of the first cell
2266:    * @param index1 the index of the second cell
2267:    *
2268:    * @return  the bounds of the rectangle that encloses both list cells
2269:    *     with index0 and index1, <code>null</code> if one of the indices is
2270:    *     not valid
2271:    */
2272:   public Rectangle getCellBounds(int index0, int index1)
2273:   {
2274:     ListUI ui = getUI();
2275:     Rectangle bounds = null;
2276:     if (ui != null)
2277:       {
2278:         bounds = ui.getCellBounds(this, index0, index1);
2279:       }
2280:     // When the UI is null, this method also returns null in the RI.
2281:     return bounds;
2282:   }
2283: 
2284:   /**
2285:    * Returns the next list element (beginning from <code>startIndex</code>
2286:    * that starts with <code>prefix</code>. Searching is done in the direction
2287:    * specified by <code>bias</code>.
2288:    *
2289:    * @param prefix the prefix to search for in the cell values
2290:    * @param startIndex the index where to start searching from
2291:    * @param bias the search direction, either {@link Position.Bias#Forward}
2292:    *     or {@link Position.Bias#Backward}
2293:    *
2294:    * @return the index of the found element or -1 if no such element has
2295:    *     been found
2296:    *
2297:    * @throws IllegalArgumentException if prefix is <code>null</code> or
2298:    *     startIndex is not valid
2299:    *
2300:    * @since 1.4
2301:    */
2302:   public int getNextMatch(String prefix, int startIndex, Position.Bias bias)
2303:   {
2304:     if (prefix == null)
2305:       throw new IllegalArgumentException("The argument 'prefix' must not be"
2306:                                          + " null.");
2307:     if (startIndex < 0)
2308:       throw new IllegalArgumentException("The argument 'startIndex' must not"
2309:                                          + " be less than zero.");
2310: 
2311:     int size = model.getSize();
2312:     if (startIndex > model.getSize())
2313:       throw new IllegalArgumentException("The argument 'startIndex' must not"
2314:                                          + " be greater than the number of"
2315:                                          + " elements in the ListModel.");
2316: 
2317:     int index = -1;
2318:     if (bias == Position.Bias.Forward)
2319:       {
2320:         for (int i = startIndex; i < size; i++)
2321:           {
2322:             String item = model.getElementAt(i).toString();
2323:             if (item.startsWith(prefix))
2324:               {
2325:                 index = i;
2326:                 break;
2327:               }
2328:           }
2329:       }
2330:     else
2331:       {
2332:         for (int i = startIndex; i >= 0; i--)
2333:           {
2334:             String item = model.getElementAt(i).toString();
2335:             if (item.startsWith(prefix))
2336:               {
2337:                 index = i;
2338:                 break;
2339:               }
2340:           }
2341:       }
2342:     return index;
2343:   }
2344:   
2345:   /**
2346:    * Returns a string describing the attributes for the <code>JList</code>
2347:    * component, for use in debugging.  The return value is guaranteed to be 
2348:    * non-<code>null</code>, but the format of the string may vary between
2349:    * implementations.
2350:    *
2351:    * @return A string describing the attributes of the <code>JList</code>.
2352:    */
2353:   protected String paramString()
2354:   {
2355:     StringBuffer sb = new StringBuffer(super.paramString());
2356:     sb.append(",fixedCellHeight=").append(getFixedCellHeight());
2357:     sb.append(",fixedCellWidth=").append(getFixedCellWidth());
2358:     sb.append(",selectionBackground=");
2359:     if (getSelectionBackground() != null)
2360:       sb.append(getSelectionBackground());
2361:     sb.append(",selectionForeground=");
2362:     if (getSelectionForeground() != null)
2363:       sb.append(getSelectionForeground());
2364:     sb.append(",visibleRowCount=").append(getVisibleRowCount());
2365:     sb.append(",layoutOrientation=").append(getLayoutOrientation());
2366:     return sb.toString();
2367:   }
2368: }